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        "\n# Decision boundary of label propagation versus SVM on the Iris dataset\n\n\nComparison for decision boundary generated on iris dataset\nbetween Label Propagation and SVM.\n\nThis demonstrates Label Propagation learning a good boundary\neven with a small amount of labeled data.\n\n\n"
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        "print(__doc__)\n\n# Authors: Clay Woolam <clay@woolam.org>\n# License: BSD\n\nimport numpy as np\nimport matplotlib.pyplot as plt\nfrom sklearn import datasets\nfrom sklearn import svm\nfrom sklearn.semi_supervised import LabelSpreading\n\nrng = np.random.RandomState(0)\n\niris = datasets.load_iris()\n\nX = iris.data[:, :2]\ny = iris.target\n\n# step size in the mesh\nh = .02\n\ny_30 = np.copy(y)\ny_30[rng.rand(len(y)) < 0.3] = -1\ny_50 = np.copy(y)\ny_50[rng.rand(len(y)) < 0.5] = -1\n# we create an instance of SVM and fit out data. We do not scale our\n# data since we want to plot the support vectors\nls30 = (LabelSpreading().fit(X, y_30), y_30)\nls50 = (LabelSpreading().fit(X, y_50), y_50)\nls100 = (LabelSpreading().fit(X, y), y)\nrbf_svc = (svm.SVC(kernel='rbf', gamma=.5).fit(X, y), y)\n\n# create a mesh to plot in\nx_min, x_max = X[:, 0].min() - 1, X[:, 0].max() + 1\ny_min, y_max = X[:, 1].min() - 1, X[:, 1].max() + 1\nxx, yy = np.meshgrid(np.arange(x_min, x_max, h),\n                     np.arange(y_min, y_max, h))\n\n# title for the plots\ntitles = ['Label Spreading 30% data',\n          'Label Spreading 50% data',\n          'Label Spreading 100% data',\n          'SVC with rbf kernel']\n\ncolor_map = {-1: (1, 1, 1), 0: (0, 0, .9), 1: (1, 0, 0), 2: (.8, .6, 0)}\n\nfor i, (clf, y_train) in enumerate((ls30, ls50, ls100, rbf_svc)):\n    # Plot the decision boundary. For that, we will assign a color to each\n    # point in the mesh [x_min, x_max]x[y_min, y_max].\n    plt.subplot(2, 2, i + 1)\n    Z = clf.predict(np.c_[xx.ravel(), yy.ravel()])\n\n    # Put the result into a color plot\n    Z = Z.reshape(xx.shape)\n    plt.contourf(xx, yy, Z, cmap=plt.cm.Paired)\n    plt.axis('off')\n\n    # Plot also the training points\n    colors = [color_map[y] for y in y_train]\n    plt.scatter(X[:, 0], X[:, 1], c=colors, edgecolors='black')\n\n    plt.title(titles[i])\n\nplt.suptitle(\"Unlabeled points are colored white\", y=0.1)\nplt.show()"
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